Optimizing the thermoelectric performance of zigzag and chiral carbon nanotubes

Using nonequilibrium molecular dynamics simulations and nonequilibrium Green's function method, we investigate the thermoelectric properties of a series of zigzag and chiral carbon nanotubes which exhibit interesting diameter and chirality dependence. Our calculated results indicate that these carbon nanotubes could have higher ZT values at appropriate carrier concentration and operating temperature. Moreover, their thermoelectric performance can be significantly enhanced via isotope substitution, isoelectronic impurities, and hydrogen adsorption. It is thus reasonable to expect that carbon nanotubes may be promising candidates for high-performance thermoelectric materials

High atmospheric carbon dioxide-dependent alleviation of salt stress is linked to RESPIRATORY BURST OXIDASE 1 (RBOH1)-dependent H2O2 production in tomato (Solanum lycopersicum)

Plants acclimate rapidly to stressful environmental conditions. Increasing atmospheric CO2 levels are predicted to influence tolerance to stresses such as soil salinity but the mechanisms are poorly understood. To resolve this issue, tomato (Solanum lycopersicum) plants were grown under ambient (380 μmol mol–1) or high (760 μmol mol–1) CO2 in the absence or presence of sodium chloride (100 mM). The higher atmospheric CO2 level induced the expression of RESPIRATORY BURST OXIDASE 1 (SlRBOH1) and enhanced H2O2 accumulation in the vascular cells of roots, stems, leaf petioles, and the leaf apoplast. Plants grown with higher CO2 levels showed improved salt tolerance, together with decreased leaf transpiration rates and lower sodium concentrations in the xylem sap, vascular tissues, and leaves. Silencing SlRBOH1 abolished high CO2 -induced salt tolerance and increased leaf transpiration rates, as well as enhancing Na+ accumulation in the plants. The higher atmospheric CO2 level increased the abundance of a subset of transcripts involved in Na+ homeostasis in the controls but not in the SlRBOH1-silenced plants. It is concluded that high atmospheric CO2 concentrations increase salt stress tolerance in an apoplastic H2O2 dependent manner, by suppressing transpiration and hence Na+ delivery from the roots to the shoots, leading to decreased leaf Na+ accumulation

Evaluation of the reporting quality of clinical practice guidelines on gliomas using the RIGHT checklist

Background: The reporting quality of clinical practice guidelines (CPGs) for gliomas has not yet been thoroughly assessed. The International Reporting Items for Practice Guidelines in Healthcare (RIGHT) statement developed in 2016 provides a reporting framework to improve the quality of CPGs. We aimed to estimate the reporting quality of glioma guidelines using the RIGHT checklist and investigate how the reporting quality differs by selected characteristics. Methods: We systematically searched electronic databases, guideline databases, and medical society websites to retrieve CPGs on glioma published between 2018 and 2020. We calculated the compliance of the CPGs to individual items, domains and the RIGHT checklist overall. We performed stratified analyses by publication year, country of development, reporting of funding, and impact factor (IF) of the journal. Results: Our search revealed 20 eligible guidelines. Mean overall adherence to the RIGHT statement was 54.6%. Eight CPGs reported more than 60% of the items, and five reported less than 50%. All guidelines adhered to the items 1a, 3, 7a, 13a, while no guidelines reported the items 17 or 18b (see http://www.rightstatement.org/right-statement/checklist for a description of the items). Two of the seven domains, "Basic information" and "Background", had mean reporting rates above 60%. The "Review and quality assurance" domain had the lowest mean reporting rate, 12.5%. The reporting quality of guidelines published in 2020, guidelines developed in the United States, and guidelines that reported funding tended to be above average. Conclusions: The reporting quality of CPGs on gliomas is low and needs improvement. Particular attention should be paid on reporting the external review and quality assurance process. The use of the RIGHT criteria should be encouraged to guide the development, reporting and evaluation of CPGs

Reducing greenhouse gas emissions of Amazon hydropower with strategic dam planning

Hundreds of dams have been proposed throughout the Amazon basin, one of the world’s largest untapped hydropower frontiers. While hydropower is a potentially clean source of renewable energy, some projects produce high greenhouse gas (GHG) emissions per unit electricity generated (carbon intensity). Here we show how carbon intensities of proposed Amazon upland dams (median = 39 kg CO2eq MWh−1, 100-year horizon) are often comparable with solar and wind energy, whereas some lowland dams (median = 133 kg CO2eq MWh−1) may exceed carbon intensities of fossil-fuel power plants. Based on 158 existing and 351 proposed dams, we present a multi-objective optimization framework showing that low-carbon expansion of Amazon hydropower relies on strategic planning, which is generally linked to placing dams in higher elevations and smaller streams. Ultimately, basin-scale dam planning that considers GHG emissions along with social and ecological externalities will be decisive for sustainable energy development where new hydropower is contemplated. © 2019, The Author(s)

Reconstruction of ankylotic and resected mandibular condyle by transport distraction osteogenesis

abstractpublished_or_final_versionDentistryDoctoralDoctor of Philosoph

Investigating color screening in proton-nucleus collisions with complex potentials

Wen L, Du X, Shi S, Chen B. Investigating color screening in proton-nucleus collisions with complex potentials. Chinese Physics C . 2022;46(11): 114102.Color screening and parton inelastic scattering modify the heavy-quark antiquark potential in mediums consisting of particles from quantum chromodynamics (QCD), leading to the suppression of quarkonium production in relativistic heavy-ion collisions. Owing to the small charm/anti-charm (c (c) over bar) pair production number in proton-nucleus (pA) collisions, the correlation between different c (c) over bar pairs is negligible, which makes the Schrodinger equation viable for tracking the evolution of only one c (c) over bar pair. We employ the time-dependent Schrodinger equation with an in-medium c (c) over bar potential to study the evolution of charmonium wave functions in a hydrodynamic-like QCD medium produced in pA collisions. We explore different parametrizations of real and imaginary parts of the cc potential and calculate the nuclear modification factors (RpA) of J//psi and psi/(2S ) in root s(NN) = 5.02 TeV energy p-Pb collisions at the Large Hadron Collider (LHC). Comparing strong and weak screening scenarios with experimental data in this approach, we arrive at the conclusion that color screening is weak at temperatures close to the deconfined phase transition. Moreover, the imaginary part of the potential is crucial in describing the experimental data, which is consistent with widely studied semi-classical approaches, where dissociation rates are essential